| Subject: | Stale lockfile without NFS results in uninitialized variable |
LockFile::Simple version 0.2.5, Simple.pm revision 0.2.1.5
Perl version v5.6.1
Debian stable (woody) with 2.4.27 kernel
The problem is that the $hostname variable in _acs_stale does not get initialized if you are not using NFS. This does not cause any problems in the module's behavior but it does lead to an ugly error message.
I wrote a quick little program to illustrate the problem:
#! /usr/bin/perl -w
use LockFile::Simple qw(lock trylock unlock);
my $lockfile = "./lock";
LockFile::Simple::configure(LockFile::Simple->locker(), -hold => 0,
-stale => 1);
trylock($lockfile);
Run this twice and you get the following output:
# /tmp/break-code
# /tmp/break-code
Use of uninitialized value in concatenation (.) or string at /usr/lib/perl5/LockFile/Simple.pm line 560.
UNLOCKED ./lock (stale lock by PID 5029) at /usr/lib/perl5/LockFile/Simple.pm line 182.
With my fix, you get
# /tmp/break-code
UNLOCKED ./lock (stale lock by PID 5027) at /usr/lib/perl5/LockFile/Simple.pm line 182.
My fix:
*** Simple.pm.new Thu Oct 28 13:52:28 2004
--- Simple.pm.old Thu Oct 28 13:33:43 2004
***************
*** 537,543 ****
chop($stamp = <FILE>);
close FILE;
! my ($pid, $hostname) = ("", "");
if ($self->nfs) {
($pid, $hostname) = $stamp =~ /^(\d+):(\S+)/;
--- 537,543 ----
chop($stamp = <FILE>);
close FILE;
! my ($pid, $hostname);
if ($self->nfs) {
($pid, $hostname) = $stamp =~ /^(\d+):(\S+)/;
*** Simple.pm.new Thu Oct 28 13:52:28 2004
--- Simple.pm.old Thu Oct 28 13:33:43 2004
***************
*** 537,543 ****
chop($stamp = <FILE>);
close FILE;
! my ($pid, $hostname) = ("", "");
if ($self->nfs) {
($pid, $hostname) = $stamp =~ /^(\d+):(\S+)/;
--- 537,543 ----
chop($stamp = <FILE>);
close FILE;
! my ($pid, $hostname);
if ($self->nfs) {
($pid, $hostname) = $stamp =~ /^(\d+):(\S+)/;